FIX: tree state in treeview should be preserved when saving (ISXB-966) (#1967)

* fixed selection behaviour in action tree.
* viewDataKey needs to be consistent across domain reloads

Author: smnwttbr

Packages/com.unity.inputsystem/CHANGELOG.md

@@ -27,6 +27,7 @@ however, it has to be formatted properly to pass verification tests.
 
 ### Fixed
 - Fixed default scroll speed in uGUI being slower than before. [ISXB-766](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-766)
+- Fixed selection state preserving after a save operation. [ISXB-966](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-966)
 - Fixed an issue when multiple interactions drive an action and perform during the cancelation of the current active interaction [ISXB-310](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-310).
 - Fixed an issue when generating C# class of Input Actions that contain an action map named `Debug` [ISXB-851](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-851).
 - Fixed ArgumentNullException thrown when accessing Action's bindings after changing Composite part. [ISXB-494](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-494).

Packages/com.unity.inputsystem/InputSystem/Editor/UITKAssetEditor/InputActionsEditorSettingsProvider.cs

@@ -259,7 +259,7 @@ private void BuildUI()
             // If the editor is associated with an asset we show input action editor
             if (hasAsset)
             {
-                m_StateContainer = new StateContainer(m_State);
+                m_StateContainer = new StateContainer(m_State, AssetDatabase.AssetPathToGUID(AssetDatabase.GetAssetPath(asset)));
                 m_StateContainer.StateChanged += OnStateChanged;
                 m_View = new InputActionsEditorView(m_RootVisualElement, m_StateContainer, true, null);
                 m_StateContainer.Initialize(m_RootVisualElement.Q("action-editor"));

Packages/com.unity.inputsystem/InputSystem/Editor/UITKAssetEditor/InputActionsEditorWindow.cs

@@ -226,7 +226,7 @@ private void BuildUI()
             if (m_State.m_Analytics == null)
                 m_State.m_Analytics = m_Analytics;
 
-            m_StateContainer = new StateContainer(m_State);
+            m_StateContainer = new StateContainer(m_State, m_AssetGUID);
             m_StateContainer.StateChanged += OnStateChanged;
 
             rootVisualElement.Clear();

Packages/com.unity.inputsystem/InputSystem/Editor/UITKAssetEditor/StateContainer.cs

@@ -13,10 +13,12 @@ internal class StateContainer
 
         private VisualElement m_RootVisualElement;
         private InputActionsEditorState m_State;
+        public readonly string assetGUID;
 
-        public StateContainer(InputActionsEditorState initialState)
+        public StateContainer(InputActionsEditorState initialState, string assetGUID)
         {
             m_State = initialState;
+            this.assetGUID = assetGUID;
         }
 
         public void Dispatch(Command command)

Packages/com.unity.inputsystem/InputSystem/Editor/UITKAssetEditor/Views/ActionsTreeView.cs

@@ -37,7 +37,7 @@ public ActionsTreeView(VisualElement root, StateContainer stateContainer)
             m_PropertiesScrollview = root.Q<ScrollView>("properties-scrollview");
             m_ActionsTreeView = root.Q<TreeView>("actions-tree-view");
             //assign unique viewDataKey to store treeView states like expanded/collapsed items - make it unique to avoid conflicts with other TreeViews
-            m_ActionsTreeView.viewDataKey = "InputActionTreeView " + stateContainer.GetState().serializedObject.targetObject.GetInstanceID();
+            m_ActionsTreeView.viewDataKey = $"InputActionTreeView_{stateContainer.assetGUID}";
             m_GuidToTreeViewId = new Dictionary<Guid, int>();
             m_ActionsTreeView.selectionType = UIElements.SelectionType.Single;
             m_ActionsTreeView.makeItem = () => new InputActionsTreeViewItem();
@@ -135,11 +135,6 @@ public ActionsTreeView(VisualElement root, StateContainer stateContainer)
                     var item = m_ActionsTreeView.GetItemDataForIndex<ActionOrBindingData>(m_ActionsTreeView.selectedIndex);
                     Dispatch(item.isAction ? Commands.SelectAction(item.name) : Commands.SelectBinding(item.bindingIndex));
                 }
-                else
-                {
-                    Dispatch(Commands.SelectAction(null));
-                    Dispatch(Commands.SelectBinding(-1));
-                }
             };
 
             m_ActionsTreeView.RegisterCallback<ExecuteCommandEvent>(OnExecuteCommand);